1. Field of the Invention
The invention relates to a vehicle bumper structure and a bumper absorber.
2. Description of Related Art
A bumper designed to protect a vehicle body and absorb impact in order to lessen a load applied to a pedestrian in the event of a collision with a person is provided on the front and rear of a vehicle. A bumper absorber is provided between a bumper cover and a bumper reinforcement. Also, a functional component such as a reflective plate or a sensor is also provided in the bumper. The functional plate that receives and reflects light from a vehicle from behind is provided on both the left and right of a rear bumper, for example.
A vehicle bumper described in Japanese Utility Model Application Publication No. 1-81150 (JP 1-81150 U) does not have any functional components. This bumper includes a backup beam that is attached to the vehicle body via a pair of symmetrical stays that are separated from each other, and a face member that is attached to an outer surface of the backup beam via an impact energy absorbing member. The impact energy absorbing member is formed by a pair of high-density impact energy absorbing members arranged substantially symmetrically and separated from each other by a narrower distance than the distance between the stays, and a residual low-density impact energy absorbing member.
A vehicle bumper structure described in Japanese Patent Application Publication No. 2003-146157 (JP 2003-146157 A) also does not have any functional components. This bumper structure is formed by a bumper beam that is fixed to a vehicle, body frame via a stay, a buffer provided on the bumper beam, and a bumper face arranged on an outside of this buffer. The buffer is formed by an expanded foam buffer main body that is fixed to the bumper beam, and on which a recessed portion is formed on a vehicle outside surface, and an expanded foam reinforcing buffer that is fit into the recessed portion of the expanded foam main body.
When a reflective plate is provided on the left and right of the bumper and an impact is input near the reflective plate on the bumper cover, for example, the reflective plate may deform or become damaged even if the impact is light, which may reduce the function of the reflective plate. In this case, the reflective plate must be replaced. Here, if the rigidity of the entire bumper is high, the impact transmitted to the vehicle body when an impact is input to a bumper center portion increases, which may reduce the vehicle body protecting function, or increase a load applied to a pedestrian if in the event of a collision with a person, such that the pedestrian protecting function may decrease. These problems are not only limited to a reflective plate, but also exist when a functional component other than a reflective plate is provided on the bumper. The bumpers described in JP 1-81150 U and JP 2003-146157 A do not take into account the provision of a functional component on a bumper, so the problems described above may occur.
Also, in order to keep the reinforcing buffer from falling off of the buffer main body, the reinforcing buffer must be fixed to the buffer main body by an adhesive, or the reinforcing buffer must be inserted when the expanded foam buffer main body is formed.